Numerical study on distribution of electric fields in cells induced by atmospheric helium plasmas

A model based on the volume of fluid (VOF) method and leaky dielectric theory is established to predict the deformation and internal flow of the droplet suspended in another vicious fluid under the influence of the electric field. Through coupling with hydrodynamics and electrostatics, the rate of deformation and internal flow of the single droplet are simulated and obtained under the different operating parameters. The calculated results show that the direction of deformation and internal flow depends on the physical properties of fluids. The numerical results are compared with Taylor's theory and experimental results by Torza et al. When the rate of deformation is small, the numerical results are consistent with theory and experimental results, and when the rate is large the numerical results are consistent with experimental results but are different from Taylor's theory. In addition, fluid viscosity hardly affects the deformation rate and mainly dominates the deformation velocity. For high viscosity droplet spends more time to attain the steady state. The conductivity ratio and permittivity ratio of two different liquids affect the direction of deformation. When fluid electric properties change, the charge distribution at the interface is various, which leads to the droplet different deformation shapes.

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Numerical Study of Dielectric Fluid Bubble Behavior within Diverging External Electric Fields

9th AIAA/ASME Joint Thermophysics and Heat Transfer Conference ◽

10.2514/6.2006-2915 ◽

2006 ◽

Cited By ~ 1

Author(s):

Matthew Pearson ◽

Jamal Seyed-Yagoobi

Keyword(s):

Electric Fields ◽

Numerical Study ◽

Dielectric Fluid ◽

Bubble Behavior ◽

External Electric Fields

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Numerical Study of Dynamic Behavior of Dielectric Fluid Bubbles Within Diverging, External Electric Fields

Heat Transfer, Volume 2 ◽

10.1115/imece2006-13493 ◽

2006 ◽

Cited By ~ 1

Author(s):

Matthew R. Pearson ◽

Jamal Seyed-Yagoobi

Keyword(s):

Electric Field ◽

Electric Fields ◽

Numerical Study ◽

Pool Boiling ◽

Spherical Shape ◽

Past Research ◽

Bubble Surface ◽

Uniform Electric Field ◽

Dielectric Fluid ◽

Uniform Field

Past research in the area of pool boiling within the presence of electric fields has generally focused on the case of uniform field intensity. Any numerical or analytical studies of the effect of non-uniform fields on the motion of bubbles within a dielectric liquid medium have assumed that the bubbles will retain their spherical shape rather than deform. These studies also ignore changes to the electrical field caused by the presence of the bubbles. However, these assumptions are not necessarily accurate as, even in the case of a nominally uniform electric field distribution, bubbles can exhibit considerable physical deformation and the field can become noticeably affected in the vicinity of the bubble. This study explores the effect that a non-uniform electric field can have on vapor bubbles of a dielectric fluid by modeling the physical deformation of the bubble and the alteration of the surrounding field. Numerical results show that the imbalance of electrical stresses at the bubble surface exerts a net dielectrophoretic force on the bubble, propelling the bubble to the vicinity of weakest electric field, thereby enhancing the separation of liquid and vapor phases during pool boiling. However, the proximity of the bubble to one of the electrodes can considerably alter the bubble trajectory due to an attractive force that arises from local distortions of the potential and electric fields. This phenomenon cannot be predicted if bubble deformation and field distortion effects are neglected.

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Radiation Problems Accompanying Carrier Production by an Electric Field in the Graphene

Universe ◽

10.3390/universe6110205 ◽

2020 ◽

Vol 6 (11) ◽

pp. 205

Author(s):

Sergei P. Gavrilov ◽

Dmitry M. Gitman ◽

Vadim V. Dmitriev ◽

Anatolii D. Panferov ◽

Stanislav A. Smolyansky

Keyword(s):

Electromagnetic Field ◽

Electric Field ◽

Electric Fields ◽

Strong Field ◽

Numerical Study ◽

Spectral Composition ◽

General System ◽

External Electromagnetic Field ◽

Quantum Radiation ◽

Quantized Electromagnetic Field

A number of physical processes that occur in a flat one-dimensional graphene structure under the action of strong time-dependent electric fields are considered. It is assumed that the Dirac model can be applied to the graphene as a subsystem of the general system under consideration, which includes an interaction with quantized electromagnetic field. The Dirac model itself in the external electromagnetic field (in particular, the behavior of charged carriers) is treated nonperturbatively with respect to this field within the framework of strong-field QED with unstable vacuum. This treatment is combined with a kinetic description of the radiation of photons from the electron-hole plasma created from the vacuum under the action of the electric field. An interaction with quantized electromagnetic field is described perturbatively. A significant development of the kinetic equation formalism is presented. A number of specific results are derived in the course of analytical and numerical study of the equations. We believe that some of predicted effects and properties of considered processes may be verified experimentally. Among these effects, it should be noted a characteristic spectral composition anisotropy of the quantum radiation and a possible presence of even harmonics of the external field in the latter radiation.

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Numerical study of the effect of electric fields on the combustion characteristics of PMMA under lateral inflow

Acta Astronautica ◽

10.1016/j.actaastro.2019.11.018 ◽

2020 ◽

Vol 167 ◽

pp. 418-428

Author(s):

Xiaolong Yang ◽

Zhijun Wei ◽

Jingjia Zhang ◽

Zelin Zhang ◽

Ningfei Wang

Keyword(s):

Electric Fields ◽

Numerical Study ◽

Combustion Characteristics ◽

Lateral Inflow

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A Numerical Study on the Large Compressive Deformations of Closed-Celled Rubber Foams

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.444-445.23 ◽

2013 ◽

Vol 444-445 ◽

pp. 23-26

Author(s):

Zhi Geng Fan

Keyword(s):

Strain Energy ◽

Potential Model ◽

Numerical Study ◽

Three Dimensional ◽

Face Centered Cubic ◽

Energy Potential ◽

Compressive Stresses ◽

Order Of Magnitude ◽

Face Centered ◽

In Cells

Three dimensional (3D) cubic models with spherical pores ranged as Face-Centered Cubic (FCC) lattices are constructed to simulate the microstructures of rubber foams with various relative densities. The Mooney-Rivlin strain energy potential model is adopted to characterize the hyperelasticity of the constituent solid from which the foams are made. Large compressive deformations of closed-celled rubber foams are calculated by the iterative algorithm. Numerical results show that with the decreasing of foam relative densities, the effects of air pressures in cells on foam compressive stresses increase. When the ratio of initial Yangs modulus of cell material to the initial air pressure in cells reaches 2 order of magnitude, the influence of air pressures in cells can neglect.

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Cyclic AMP response in cells exposed to electric fields of different frequencies and intensities

Radiation and Environmental Biophysics ◽

10.1007/bf01219337 ◽

1994 ◽

Vol 33 (2) ◽

pp. 141-147 ◽

Cited By ~ 32

Author(s):

G. Knedlitschek ◽

M. Noszvai-Nagy ◽

H. Meyer-Waarden ◽

J. Schimmelpfeng ◽

K. F. Weibezahn ◽

...

Keyword(s):

Cyclic Amp ◽

Electric Fields ◽

In Cells

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Effect of electrical stimulation on biological cells by capacitive coupling – an efficient numerical study considering model uncertainties

10.36227/techrxiv.11988216.v1 ◽

2020 ◽

Cited By ~ 1

Author(s):

Julius Zimmermann ◽

RIchard Altenkirch ◽

Ursula van Rienen

Keyword(s):

Electrical Stimulation ◽

Cell Membrane ◽

Electric Fields ◽

Biological Samples ◽

Numerical Study ◽

Cell Activity ◽

Cellular Level ◽

Capacitive Coupling ◽

Fe Method

Electrical stimulation of biological samples such as tissues and cell cultures attracts growing attention due to its capability of enhancing cell activity, proliferation and differentiation. Eventually, profound knowledge of the underlying mechanisms paves the way for innovative therapeutic devices. Capacitive coupling is one option of delivering electric fields to biological samples and has advantages with regard to biocompatibility. However, the mechanism of interaction is not well understood. Experimental findings could be related to voltage-gated channels, which are triggered by changes of the transmembrane potential (TMP). Numerical simulations by the Finite Element method (FEM) provide a possibility to estimate the TMP. For realistic simulations of in vitro electric stimulation experiments, a bridge from the mesoscopic level down to the cellular level has to be found. A special challenge poses the ratio between the cell membrane (a few nm) and the general setup (some cm). Hence, a full discretization of the cell membrane becomes prohibitively expensive for 3D simulations. We suggest using an approximate FE method that makes 3D multi-scale simulations possible. Starting from an established 2D model, the chosen method is characterized and applied to realistic in vitro situations. A to date not investigated parameter dependency is included and tackled by means of Uncertainty Quantification (UQ) techniques. It reveals a strong, frequency-dependent influence of uncertain parameters on the modeling result.

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